780 MT, question on PSU

Question

I just got this as a refurbished PC . I spoke to tech support the other day. It seems there is only one fan in the entire PC called the system fan. I had an old dimension XPS 450 for a while and it had a PSU fan . I've never seen this before . It seems to run cool by feel and works fine . I realize it's an old machine Dell told me 7 years and 7 months old by the service tag I provided. Being a refurb machine I can't really say what year it was built simply because the company who does these may use good used parts from different machines since once you order one it takes 2 days for them to build one. It looks like new inside no dust . Is this the way they cool with just one fan? I would have bought something new if I could afford it , so far I have complaints and have had a few Dell products none died in the years I've had them . I just worry about parts if I need them at some point.

speedstep · Accepted Answer

The power supply fan is Energy Star so it only vents at specific temperatures and it slows down when its idle to save energy.

beamermt79 · Answer

I took a look at the manual and it looks like a BTX system (if I remember correctly). Those are designed to draw cool air into the case and blow hot air out the air vents sometimes negating the need for a bunch of fans. I had a dimension that was like that and I dont remember if the PSU had a fan or not. If you look in the PSU air hols and don't see any fans (sometimes they are small or super quiet) I wouldn't worry about it myself.

speedstep · Answer

There are 2 FANS. The front intake and the power supply that vents out the back.&#xa0;cooling detail

blues90 · Answer

I only see one fan . I didn't look at the PCU when I had the cover off yet I don't feel any air out of the rear of the PCU and don't see any fan as most PSU's I've seen have , most I've seen have a fan at the rear you can see some like the PCU I replaced in the Acer I have has 2 fans because the original was starting to act up PC would not boot all the time and was 250 watt the new PCU was 480 watt with dual fans same 80 mm size . That was an ATX case this Dell is a BTX case. I'm not sure what the watt rating is on the Dell 780 MT I forgot to look it's either 307 or 255 which is not much different. I see some of the new Dell towers use a laptop type power supply.

blues90 · Answer

It is a BTX case . it may just have the one fan dell calls the system fan which cools the CPU and the PCU. I'll have to look . I would think if the PCU had a fan I would feel air flow out the rear and I don't .

blues90 · Answer

You are correct . I removed the cover just to see what it has installed and can see it's a 255 watt PCU and does have a fan inside the PCU it's facing the front of the tower . Rather than pull air through the PCU as a rear mounted fan it forces air through . So far I have not heard or felt it come on yet the PCU is very clean inside.

The Place I bought it from who refurbishes PC's did a real good job . I think they test every part and clean every part plus they added new HP 8 GB ram 4 cards one in each slot. I see dates in the case of 2016

Some how it detected my Dell IN1910N flat screen monitor which is VGA only and uses a windows driver since it's running windows 10 Pro x64. I'm just using the built in VGA on the board . It is a forced PNP hardware.

I would like to add a video card in the PCI express x16 yet I'm not sure which one. I don't need a great one with another fan . The part that is for me confusing is I have a video card in my 2006 Acer veriton m261 tower. I know it's an ADM Radeon yet recall ATI somewhere which may be the driver . If I recall it's a x series and don't know it will work in the dell . Has no fan and a VGA plus a round port .

I took photo's of the inside just to know what it has

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780 MT, question on PSU

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